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Testing Algorithms for Finite Temperature Lattice QCD

M. Cheng·M. A. Clark·C. Jung·R. D. Mawhinney
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Abstract

We discuss recent algorithmic improvements in simulating finite temperature QCD on a lattice. In particular, the Rational Hybrid Monte Carlo(RHMC) algorithm is employed to generate lattice configurations for 2+1 flavor QCD. Unlike the Hybrid R Algorithm, RHMC is reversible, admitting a Metropolis accept/reject step that eliminates the $\mathcal{O}(δt^2)$ errors inherent in the R Algorithm. We also employ several algorithmic speed-ups, including multiple time scales, the use of a more efficient numerical integrator, and Hasenbusch pre-conditioning of the fermion force.

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M. Cheng, M. A. Clark, C. Jung, R. D. Mawhinney. 2006-08-23. Testing Algorithms for Finite Temperature Lattice QCD. https://doi.org/10.1016/j.nuclphysa.2006.11.149

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